On August 21, 2003, about 1930 Alaska daylight time, a tailwheel and tundra tire-equipped Piper PA-18-160 airplane, N2608S, sustained substantial damage when the left main landing gear collapsed, and the left wing struck the runway, following a loss of control during the landing roll at the Tazlina airstrip, located about 30 miles east of Glennallen, Alaska. The Title 14, CFR Part 91 personal flight operated in visual meteorological conditions without a flight plan. The solo commercial pilot was not injured. The flight departed a remote off-airport site near the Hallett River at 1815, and the destination was the Tazlina airstrip. During a telephone conversation with National Transportation Safety Board investigator-in-charge (IIC) on August 21 at 2142, the pilot related the accident airplane has 29-inch tundra tires, and that prior to landing at Tazlina, he had departed an off-airport site near the Hallett River without incident. He said he was landing on runway 13 with a calm wind, and that shortly after touchdown on the gravel runway, the airplane went quickly to the right. He said he was unable to keep the airplane aligned with the runway, and as it continued to the right, the left main landing gear collapsed, and the left wing contacted the ground, damaging the rear spar. The pilot said he was unaware of any preaccident mechanical problems with the airplane, but that he and an aviation mechanic were going to check the brakes to be certain that the right brake didn't lock during the landing roll. As of December 12, 2003, the pilot had not contacted the NTSB IIC regarding any mechanical issues with the airplane, and the IIC's attempts to contact the pilot were unsuccessful.